let bool: boolean = false;
console.log(bool)

let age: number = 18;

let username: string = "ShirDon Liao";

let numbers: number[] = [1, 6, 8];

let usernames: Array<string> = ["ShirDon", "Jack", "Barry"];

let customer: [string, number] = ["ShirDon", 18];

enum Direction {
    East,
    West,
    South,
    North
}
let myDirect: Direction = Direction.East;

let num: number = 188;

function logInfo(): void { console.log("void类型!"); }